1. Field of the Invention
The present invention relates generally to a screen for displaying, on an enlarged scale, an image projected by a projecting device such as a projector, and in particular, but not exclusively, to a portable screen device that is easy to carry and can be installed on a floor, a table, or the like.
2. Description of the Related Art
An image projected by a projector is generally displayed, on an enlarged scale, on a reflection type screen. Of such screens, some are generally accommodated in a housing mounted on a ceiling or a side wall, and are electrically or manually extended as occasion demands. Hanging screens or screens with a tripod are used by hanging or locating them at a desired place.
Recently, due to the increasing number of meetings or conferences in companies or offices, there is an increased demand for a portable screen device with a simple structure that is easy to carry with a projector which can be installed on a floor, a desk, or a table in a conference room to display an image projected by the projector. Due to this demand, portable screen devices are today available in which a screen is wound around a roll stored in housing. When such screen devices are in use, the housing is initially installed at a desired place, and the screen is subsequently extended by, for example, an extension means somewhat similar to a pantograph by the action of the biasing force of a spring mounted therein, or the screen is fastened to a column attached to the housing (for example, refer to JP Laid-open Utility Model Publication No. 6-36048).
There is also an increased demand for a portable screen device for in home use because of increased use of projectors for projecting a TV picture.
However, a portable screen device for home use must to be small and light in weight so that it can be easily carried by a woman or a child. Conventionally, when a portable screen device is put into a storage position, the screen is wound first and then the column is contracted; or the column is contracted while the screen is engaged with the column and, thereafter, the screen is removed from the column and wound. In the former case, the screen is manually removed from the tip end of the column and then is wound and, thereafter, the respective tubular members constituting the column are released from the engagement and pushed into one another to contract the column. In the latter case, the column is contracted at the back side of the screen and, then, the screen is removed from the tip end of the column and wound. In both cases it is difficult to put the screen device into a storage position. In particular in the former case, even an adult can not reach the tip end of the column to remove the screen from the column, because screen sizes have increased to 80 inches, 100 inches, and the like. The latter method, is problematic because a user must move to the back side of the screen to contract the column, and when the screen device is installed near a wall, the user must either move the screen device, or perform operations in a narrow space. Therefore, there is also a need for a simple structure which facilitates the operations for putting screen devices into a storage position, such as housing the screen in the storage case and contracting the column and the like.